区域土壤污染普查监测点位布设方法探讨

以江苏无锡和镇江两地为例,比较了8 km×8 km网格和4 km×4 km网格两种布点方式下,所得到的土壤中11种无机元素（As、Cd、Cr、Cu、Hg、Mn、Ni、Pb、Se、V、Zn）以及4类有机污染物（有机氯农药、多环芳烃、多氯联苯和酞酸酯类）的监测结果。按顺序统计量排列,发现多数无机元素和有机污染物的含量,从最小值到90%值总体吻合,而在90%值以上,两种布点方式的调查测定值出现差异,说明对于污染物含量低的地区,8 km×8 km网格和4 km×4 km网格获得的结论基本一致,而污染物含量高的     

Intra-seasonal Features of an Extreme High Temperature Event in 2011 in Eastern China and Its Atmospheric Circulation

Based on the daily maximum air temperature data from the China Meteorological Data Network and the NCEP/DOE reanalysis data, the intra-seasonal circulation and evolution of an extreme high temperature event (EHTE) in the middle reaches of the Yangtze River (MYR) from August 9-21, 2011 were explored, as well as the influence of diabatic heating on the position variation of the Western Pacific subtropical high (WPSH). Results show that the daily Tmax in the MYR exhibits a vigorous intraseasonal oscillation (ISO) of 10-25 days in the extended summer of 1980-2018. The main factors affecting the EHTE in the summer of 2011 are the low-frequency wave train propagating southeastward in the mid-latitude of the upper troposphere and the low-frequency anticyclone moving northwestward in the low- latitude of the mid-lower troposphere. The diagnosis of 925hPa thermodynamic equation indicates that the ISO features of the Tmax in the core region is determined by the intra-seasonal variation of the adiabatic variation. In addition, the variations of the WPSH correspond well to the distribution of apparent heat source. In the early stage of the high temperature process, the apparent heat source in the north of the Bay of Bengal is a certain indicator for the westward extension of the WPSH.     

王集勘查区地质构造特征及对煤层的影响

通过施工钻孔研究,结合周边资料,对王集勘查区地质构造特征进行了描述,分析了研究区构造对含煤建造、煤层厚度和煤炭资源勘探的影响,认为构造对煤层的形态和分布有控制作用,区内断层对煤层具有破坏作用,下步勘查工作可加强本区断层的研究。     

物理干扰对修复压实土壤特性的影响

采用人工耕作松土,研究了物理干扰对修复压实土壤特性的影响。结果表明,实施物理干扰后的土壤,其土壤容重减小,孔隙度增大,土壤特性能得到一定程度的修复,但对压实比较严重的0～10 cm浅层土壤,修复较慢,对压实比较轻的10 cm以上土层的土壤,修复较快。     

《流体力学》连续方程推导的巧方法

针对柱坐标系和球坐标系下《流体力学》中连续方程形式复杂、理解不便的特点,采用欧拉控制体方法,把“质量通量”整体作为一物理量,从而巧妙地推导了这两类连续方程,该过程物理意义明确、数学算法简单,有助于学生理解。     

恒星的演化及其稳定性

一、引言 当提到原子时,在我们头脑中就有一个清晰的图象:一个中心核和一群环绕着它的电子。我们将原子设想为,其大小由埃(10~(-8)厘米)来量度的小物体;我们也知道存在一百多种不同的原子。当然这种图象需要定量化,在现代量子理论中才被精确化。这整个理论的成功可追溯到两个基本事实。首先,氢原子基态的玻尔半径,即     

现在天气现象编报91-99时W1W2的编码方法

现在天气现象(WW)编报91-99时,过去天气现象(W1W2 )的编报方法,《地面气象电报》虽有说明,但没有具体的选码方法,另外,对怎样判断某降水时段是否属于雷暴期间的降水,书上也说得不够详细.加上实际情况错综复杂,有些观测员在碰到这类问题时往往很难确定如何编码.笔者经过对特殊编报规定的认真分析,将书上的特殊编报规定转化成编码方法,叙述如下:……